DHT’s application earlier this year set off the most intense skirmish over historic preservation in Miami in recent years. It pits a band of preservationists, architects, academics and historians against a wealthy corporation and a downtown establishment that, although wary of casino gambling, is eager to see redevelopment of the Herald site, most of which consists of parking lots.

Some critics have said DHT is only trying to block gambling. But under laws governing historic preservation, designation does not affect how the building is used. So long as its exterior shell is preserved, Genting could add to the building or put a tower over it, and the company would remain free to erect new buildings on the balance of its property.

The battle is playing out on the leading edge of national preservation efforts, which are increasingly focused on salvaging important mid-20th Century Modernist buildings whose often-severe design, like the Herald building’s, is not broadly popular and considered “ugly’’ by many.

To supporters of designation, who say their case is overwhelming, it’s also a test of the resolve of the city’s preservation board. In October, the board voted narrowly, by a 6-4 margin, to consider the building for designation. The board has the final say, though a designation can be appealed to the Miami City Commission — something Genting is widely expected to do if designation were to be approved Monday.

Critics say the city has been too willing to allow demolition of historic buildings for promised new development that sometimes fails to materialize, especially in the Omni and Edgewater neighborhoods around the Herald building. Large swaths of those areas have been vacant for years because of the widespread destruction of some of the city’s original and most distinct buildings, including Mediterranean Revival commercial blocks and homes.

In contrast, they say, Miami Beach has attracted billions of dollars in investment by preserving its historic stock of buildings, at least along the Atlantic shoreline, while allowing developers to add substantial towers and new wings to the properties. Many of those were once as unpopular as the Herald building is for some today.

The Beach has in recent years designated MiMo-centric historic districts that include massive hotel properties, including the storied — and once derided — Fontainebleau Hotel.

If the Herald building were on the Beach, preservationists say, it would almost certainly win designation today.

“When the fight started over Art Deco in the 1970s, people thought it was ugly. Now it’s beloved,’’ said Charles Urstadt, chairman of the Miami Design Preservation League, which is credited with saving what is now South Beach and is supporting designation of the Herald building. “It’s an economic engine of Miami Beach. To call the Herald building ugly is not part of the decision to be made. Ugly or beauty is not part of it. It’s not a matter of popularity.

“There is no question in anybody’s mind that the Herald building has both architectural merit and historic merit. The criteria are very clear and this certainly meets it.’’

That’s not to say there is complete agreement over the Herald building even among preservationists and fans of Modern design. Some prominent preservationists, including those attempting to save the Miami Marine Stadium, have conspicuously stayed out of the fight.